Cannabis is a substance derived from the hemp plant (Cannabis indica or Cannabis sativa); the leaves and stalks of these plants may be referred to as hashish or marijuana. The term cannabis may refer to the female flowering heads of hemp, or to a resin obtained from the flowering heads that may also be referred to as cannabin. Derived materials include cannaboid, an alkaloid cannabine, and an oil cannabinol. In this specification these, and other derivatives, are referred to generically as cannabis.